I was 17 at the time and my brother was 15 or 16. We were home alone often and at the time, we were pretty close. I walked by my brother's room, which was missing a doorknob at the time, and due to my inquisitive nature I took a peek through the hole.
To my surprise, I saw my little brother butt-naked, sprawled out on his bed furiously jerking his boner! It looked about 5 inches or so and pretty thin. I watched for a minute or so but I started to laugh and didn't want him to hear me so I went back into my room across the hall. Of course I called all of my friends and told them what I had seen.
It wasn't the first time I saw him aroused. When he was about 11 or so, I decided to dress him up in pantyhose as a joke. He always knew I was in charge. As I slid them up his legs I encountered a little stiffy. It was the first time I ever saw a boner in real life but I had heard about them before. I guess it was the first one I ever touched also, as I just grabbed it and crammed it into the tight pantyhose, sticking straight out at me.
About a year after I caught him jerking off, I started to suspect that somebody was looking through my underwear drawer. I began to arrange all my panties in specific positions so I could determine if my suspicions were correct. Almost every day I noticed that not only was somebody moving all of my panties, but some of them were all stretched out in the crotch. I knew that it could not have been my boyfriend so the likely culprit was my little brother.
I tried to ignore the situation, hoping that he would just stop but he didn't. He tried to be careful but he didn't know that I even suspected anything so he just kept on wearing my beautiful panties.
One day he came out of the shower and noticed my car wasn't in the driveway-what he didn't know was that I had lent it to a friend. I was downstairs eating. I heard the floorboards creak above me, which was my room!
I crept up the stairs and peeked around the corner into my room. I saw my brother in my underwear drawer while wearing my favorite lowrise panties! He was fully aroused, with his dick poking straight out, stretching out the crotch. He was so concerned with browsing for another pair that he didn't even notice that I was now standing in the doorway, speechless.
'Oh my God!', I screamed. His jaw dropped to the floor and he immediately attempted to cover up his erection. I told him that it was disgusting and that he is sick. He made a break for the door but I was standing in the way and refused to move in anger. I wanted him to regret this day. I told him that I was not only going to tell our parents, but all of his and my friends.
I had him by the balls, so to speak. I ordered him to stand still with his arms at his side and shut up. I just stood there silently staring to embarrass him. He turned beet red and stood there with his boner now starting to slip out of my panties and I saw it throbbing as it stretched the fabric. I told him he had to stand there until his dick got soft becase I wanted my underwear back and I didn't want to see his hard on.
After about 10 minutes it was still hard! I glanced at it every minute or so just to check.
I took a couple of polaroids of him to keep as insurance. I was sitting on my bed and the little perv was looking down my shirt at my d-cup boobs! I think that's why he was so hard. I actually took it as a compliment and began to enjoy it. Now I just wanted to see how long I could 'keep it up' for. I ordered him to change into a pair of skimpy thongs, knowing that his engorged dick would not be able to fit in those.
I turned away from him told him I didn't want to see anything hanging out when I turned back around. After 10 seconds I turned back around to see him strugling to fit his hard dick into the thongs. It was a lost cause. He stood there at full attention looking helpless. He said it wouldn't go down because he was nervous. I knew that it wouldn't go down because he was checking out my body in my little outfit.
As I got a clear view of his dick, I realized my little brother was not so little anymore. His boner was at least 7.5 inches and kind of thick. I had seen a dozen penises or so but had never seen one that big. It just wouln't get soft!
Finally it dropped down and he said 'Can I go now?' I told him to hold on and grabbed the thong, down by his ankles, being sure he got a good view down my loose shirt. As I stood up, so did his penis. In fact, every time his erection subsided, I would tease him and eventually started standing within inches of him until I could see his dick start to throb and stand straight out again.
Within an hour or so, I was in my bra and panties tormenting him and telling him that he was disgusting for being aroused by his sister. I then decided to pull out a pair of pantyhose and put them on him. I kind of wanted to see that big dick in them, reinacting my first boner experience. Just as the last time, as I pulled them up on him I was confronted with a hard on. I pulled out the waistband and stretched it around his hard dick. I grabbed the fabric around his crotch and made his dick stick straight out. I ordered him into the bathroom so I could keep an eye on him while I peed. When he refused, I got pissed off and grabbed him by his boner to drag him with me. After a couple of steps my hand got wet and warm and slipped off of his dick. Yup, my little brother had sprayed a load all over my hand, right through the pantyhose.
Horrified, and as I yelled 'Gross!', he ran into his room and closed the door. I only touched it for a couple of seconds and he came! I didn't even jerk it, just grabbed it.
Again, I took it as a compliment and jilled in the shower as I washed his cum off of me. Obviously, that changed our relationship. I kept the pictures just so he knows I'm in control. From time to time I will go into his room and model lingerie that I buy for my boyfriends. I force him to drop his pants as I try different things on, seeing what gets the longest lasting boner. I don't think he wants to do it, but he still gets hard! Sometimes I make him show my friends his dick. They like being able to observe penises. We also have contests to see who can get him to stay hard for the longest time without touching him. I always win! They even pose in pictures with his prick as long as they don't tell anyone who it is. And he hasn't touched a pair of my panties since.